01 · Chong and Ren
An insight into menstrual cramps
冲任二脉 · 痛经
Low-belly cramps often show when Qi and Blood shift sharply in the Chong and Ren channels (冲任二脉). Dull ache late in the period reads deficiency (不荣则痛). Sharp or distending pain early in the flow reads excess blockage (不通则痛).
Monthly cramps without another disease are the common pattern. Pain tied to endometriosis, adenomyosis, uterine fibroids, or pelvic infection is usually more severe. The pattern was first recorded in the General Treatise on the Cause and Symptoms of Diseases (诸病源候论) in 610 CE.